Dear Sirs,
When I want to eliminate a variable of a system of DEQ, I can't
eliminate its derivatives:
In[1]:=
Eliminate[{a y[z]-b s'[z]==0,d s[z]+f y'[z]+g s'[z]+h
s''[z]==0},{y[z]}]
Out[1]:=
d s[z]== -g s'[z]-f y'[z]-h s''[z]
depends on y'[z] when in fact it is possible to eliminate it deriving
the first equation and putting them in the second one.
I will agree any help.
Jaume